UCGE Reports Number 20153 Department of Geomatics Engineering A Java Implementation for Open GIS Simple Feature Specification (URL: http://www.geomatics.ucalgary.ca/links/GradTheses.html) by Chuanyun Fei October 2001 THE UNIVERSITY OF CALGARY A JAVA IMPLEMENTATION FOR OPEN GIS SIMPLE FEATURE SPECIFICATION by CHUANYUN FEI A THESIS SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE DEPARTMENT OF GEOMATICS ENGINEERING CALGARY, ALBERTA October, 2001 Chuanyun Fei 2001 ABSTRACT Distributed GIS is the trend in the current GIS community. It has been recognized that interoperability is one of major issues in the distributed geocomputing environment. To respond to non-interoperability problem, OGC creates a series of specifications to form an open framework as GIS standards. These standards are increasingly accepted by GIS software vendors, geodata and geoprocessing providers, and users. This research focuses on an implementation of OpenGIS Simple Features Specification in the Java computing platform, which is an important family member of OGC’s specifications. A Java version Implementation Specification for OpenGIS Simple Features is designed in this research based on the review and analysis of the OGC Abstract Specification, OGC implementation specifications for SQL, OLE/COM and CORBA, and other related works done by other organizations. The Geometry Data Model, the spatial component of OpenGIS Simple Features, was designed and implemented following the new Implementation Specification. The Template Union Model for buffer operation was introduced, and some new algorithms were developed. The reasonable geometry object classification logic made the designed model more extendable and implementable. The UML technology and Java standards applied in the design and implementation procedures made the model more maintainable and distributable. An easy- to-use Conformance Testing Suite was also developed to check whether or not each implementation is strictly compatible with the requirements of the new Simple Features Implementation Specification. The application example demonstrated that the design and implementation of the designed specification in this thesis are successful. iii ACKNOWLEDGEMENTS I wish to express my deep gratitude to my supervisor, Dr. C. Vincent Tao, for his advice, guidance, encouragement, and support throughout my graduate studies. I am also grateful to Dr. Marina Gavrilova, Department of Computer Science, U of C, for her valuable suggestions about the algorithms of computational geometry during my thesis research. My appreciation also goes to Mr. Shuxin Yuan for his contribution in GeoEyeTM 1.0, and postdoctoral fellows, Mr. Chaowei Yang and Mr. Quanke Wang, for their cooperation, discussions and suggestions in the development and improvement of the thesis related software, and Mr. Andrew Hunter, Mr. David Alton and Mr. Suen Lee for the proofreading of the draft of this thesis. I am also grateful to the secretaries, technicians and computer specialists and graduate students in the Remote Sensing and GIS Lab of the Department of Geomatics Engineering, who, in one way or other, helped me during my graduate studies. Finally my appreciation and thanks go to my family, my dearest wife, Xinxin Zhang for their endless love, understanding, devotion and support, which make this thesis possible. iv TABLE OF CONTENTS APPROVAL PAGE ...................................................................................................................... ii ABSTRACT..................................................................................................................................iii ACKNOWLEDGEMENTS ........................................................................................................ iv TABLE OF CONTENTS ............................................................................................................ iv LIST OF FIGURES ...................................................................................................................viii LIST OF TABLES ........................................................................................................................ x CHAPTER 1 INTRODUCTION ............................................................................................ 1 1.1 Research Background........................................................................................................ 1 1.2 Objectives and Limitations................................................................................................ 8 1.3 Outline ............................................................................................................................. 10 CHAPTER 2 INTEROPERABILITY.................................................................................. 12 2.1 Background...................................................................................................................... 12 2.1.1 GIS Trend.................................................................................................................. 12 2.1.2 Overview of Interoperability..................................................................................... 15 2.2 Interoperability Levels..................................................................................................... 19 2.3 Interoperability Approaches ............................................................................................ 23 2.3.1 Overview................................................................................................................... 23 2.3.2 OGC’s Approach ...................................................................................................... 25 2.4 Summary.......................................................................................................................... 31 CHAPTER 3 RESEARCH METHODOLOGY.................................................................. 32 3.1 Existing Work Review..................................................................................................... 32 3.2 Design And Implementation............................................................................................ 33 3.3 Testing Suite.................................................................................................................. 235 3.4 Case Study ....................................................................................................................... 35 CHAPTER 4 EXISTING WORK REVIEW....................................................................... 37 4.1 OGC's Implementation Specifications ............................................................................ 37 4.2 Other Existing References............................................................................................... 39 CHAPTER 5 JAVA IMPLEMENTATION ........................................................................ 46 v 5.1 General Logical Model Design........................................................................................ 46 5.1.1 Design Criteria .......................................................................................................... 46 5.1.2 Geometry Entity Design............................................................................................ 47 5.1.3 Geometry Entity Classification Criteria.................................................................... 52 5.2 Geometry Data Model Design......................................................................................... 53 5.2.1 Abstract Geometry Data Model Design.................................................................... 54 5.2.2 Geometry Data Model............................................................................................... 55 5.2.3 Factory Design .......................................................................................................... 57 5.3 Geometry Implementation............................................................................................... 57 5.3.1 Functions ................................................................................................................... 58 5.3.2 Geodata Storage ........................................................................................................ 79 5.4 Characteristics Analysis .................................................................................................. 83 CHAPTER 6 TESTING SUITE ........................................................................................... 85 6.1 Objectives ........................................................................................................................ 85 6.2 Testing Suite Design........................................................................................................ 86 6.2.1 Testing Suite Generation........................................................................................... 86 6.2.2 Testing Procedure ..................................................................................................... 86 6.2.3 Design Considerations .............................................................................................. 86 6.2.4 Components of Testing Suite.................................................................................... 87 6.3 Implementation................................................................................................................ 88 6.4 Issues ..............................................................................................................................